"We tend to overestimate the effect of a technology in the short run and underestimate the effect in the long run," said the late American futurist and engineering researcher Roy Amara, a maxim known as Amara's law.

It takes more than a long-term view to understand why Facebook continues to invest heavily in virtual reality.

It also takes optimism -- to believe that VR will succeed the PC and the smartphone as the next widespread computing platform when it's still a niche technology.

In other words, it takes the kind of unbounded confidence that has helped Facebook CEO Mark Zuckerberg make expensive bets on a future that most don't see.

"The future is built by the people who believe it can be better," Zuckerberg told more than 2,000 developers gathered for the company's annual VR confab in San Jose on Wednesday.

Zuckerberg is betting that the future of VR will be, like Facebook itself, "social," with users sharing experiences across distances.

"We are legitimately excited about the future. We're committed to making it happen," Zuckerberg said.

Yet even he admits that many don't see it that way.

"People say VR is isolating and anti-social. I actually think it's the opposite," he told the crowd. "Saying VR is isolating because it's immersive is a very narrow view of the world you're all building," he told the crowd.

"The most important technologies don't start off mainstream. A lot of them seem maybe even too crazy or complex to start."

That level of commitment will be needed given that the first day of the Oculus Connect conference raised as many questions as it answered about the company's VR strategy.

For example, the company unveiled two stand-alone headsets, the Go and the Santa Cruz, re-affirming its commitment to hardware for now.

But while they will be untethered from smartphones or PCs, the pricing of the first and the timing of the second left some developers at the show scratching their heads.

"I'm excited to try it, but I don't understand what market niche they're going for" with the Go, said Tyler Hopf, creative director of Iris VR, a 25-person independent development shop based in New York.

That's because the low end of the market is already being served by hardware makers like HTC and Samsung, who've sold far more units than Facebook has of the Oculus Rift.

Meanwhile, the release date of the Santa Cruz headset was something that Facebook executives at the show wouldn't commit to.

That left some wondering whether the product — now a prototype only — may arrive after others in the industry have moved on to sleeker hardware like digital glasses.

That's a crucial question, because Facebook's 'walled-garden' approach of producing a proprietary system, rather than one that works easily with others, will force developers to choose between platforms.

That could slow down the pace of development and push out the date of when — or if — VR becomes widely adopted.

"People see how much they're investing in systems, but they can do a lot more in making VR development open," said Francisco Camberos, associate creative director of TVGla, a Los Angeles-based ad agency that counts Hulu and Netflix among its clients.

Oculus allowed a CNBC reporter to test the Santa Cruz headset, which allows the user to physically move around the room, thanks to additional sensors.

This freedom of movement greatly enhances the immersive feeling of the experience.

Yet the cost of developing the technology will almost surely drive up the cost of the system, whenever it ships.

And that could render it a more expensive choice attractive mostly to niche users like hardcore gamers.

Indeed, for all the talk of the the many ways VR will change the world at the show, most of the investment and best-selling titles remain immersive games.

Still, Oculus executives say they are committed to Zuckerberg's strategy.

"If we nail 'social,' people will come to the device," Oculus vice president of content Jason Rubin told CNBC in an interview. That's "the most important thing for driving VR adoption...Mark recognized that early on," Rubin said.

Zuckerberg is pushing forward with his vision in spite of the technology's current shortcomings.

"Yeah, today, we need this big headset and that's not great…we're working on it," he said during his keynote.

Yet "VR can put people first…Virtual reality is about imagining the world as it could be," Zuckerberg said.

Correction: An earlier version of this story misspelled Tyler Hopf's last name.